Press-room / Digest
Are there specific antibodies against Neu5Gc epitopes in the blood of healthy individuals?
Human biosynthetic machinery only synthesizes N-acetylneuraminic acid (Neu5Ac), while the other mammals synthesize both it and N-glycolylneuraminic acid (Neu5Gc), i.e., the latter is a potential xeno-antigen for humans. At the same time, Neu5Ac from the eaten meat of animals is metabolically active and found in human glycans, so it was believed that humans have antibodies to Neu5Gca2-3Galb1-4GlcNAc. Researchers from the Laboratory of Carbohydrates IBCH RAS systematically studied the repertoire of antibodies from healthy donors and found (see Glycobiology) that they have practically no antibodies to this glycan. At the same time, antibodies to Neu5Gc-containing glycans were found in patients with multiple sclerosis (see Neurology: Neuroimmunology & Neuroinflammation), which may be a marker of this disease.
A novel method of fluorescent labeling of proteins in living cells using short α-helices
Researchers from the Laboratory of Biophotonics and the Group of molecular tags for optical nanoscopy, IBCH RAS, together with foreign colleagues developed a novel method of fluorescent labeling of proteins in living cells using short α-helices (so-called K/E-coils), which tend to interact with each other. The small size of the labels (only 2-3 kDa) should decrease the impact on the native dynamics of studied proteins. In comparison to popular covalent labels, K/E-coils can increase the resistance of labeling to photobleaching by an order of magnitude due to the continuous exchange of probes. In addition, this method makes it possible to observe the target proteins almost immediately after their synthesis without the need to wait for the long-term maturation of fluorescent proteins. This work was supported by the RSF grant 16-14-10364. Results are published in Cellular and Molecular Life Sciences.
Deciphering Ribosomes’ Actions in Living Cells
Researchers from the Laboratory of Bioinformatics Approaches in Combinatorial Chemistry and Biology IBCH RAS, in collaboration with Irish colleagues, recently published a review in WIRES RNA that compiles the computational approaches, software tools, and data resources that have been developed over the last ten years for ribosome profiling data processing and analysis. The review outlines all the necessary steps involved in the initial processing of the data and highlights potential sources of artifacts and explains how to avoid them. Researchers can use this comprehensive guide to choose the most suitable tool depending on their specific goals and a preferable computational platform. Learn more
The new method for T-cell receptor alpha chain clonality assessment can be used for minimal disease monitoring in leukemia
A group of scientists from Laboratory of Comparative and Functional Genomics in collaboration with colleagues from Masaryk universities and Dmitry Rogachaev center for pediatric hematology, oncology and immunology developed a method for clonality assessment of human T-cell receptor alpha chain gene rearrangements. They showed for the first time that such rearrangements are found in approximately 50% of the tumors of patients with various oncohematological malignancies. The new method will improve minimum residual disease monitoring for the treatment of leukemia. Results of the study are published in British Journal of Haematology. Learn more
A Solid‐State Protein Junction Serves as a Bias‐Induced Current Switch
A sample-type protein monolayer, that can be a stepping stone to practical devices, can behave as an electrically driven switch. This feat is achieved using a redox protein, cytochrome C (CytC), with its heme shielded from direct contact with the solid-state electrodes. Ab initio DFT calculations, carried out on the CytC–Au structure, show that the coupling of the heme, the origin of the protein frontier orbitals, to the electrodes is sufficiently weak to prevent Fermi level pinning. Thus, external bias can bring these orbitals in and out of resonance with the electrode. Using a cytochrome C mutant for direct S–Au bonding, approximately 80% of the Au–CytC–Au junctions show at greater than 0.5 V bias a clear conductance peak, consistent with resonant tunneling. The on–off change persists up to room temperature, demonstrating reversible, bias-controlled switching of a protein ensemble, which, with its built-in redundancy, provides a realistic path to protein-based bioelectronics. Results of the study are published in Angewandte Chemie International Ediion.